Just looked at the USGS gage: 665 cfs.
To get a raft through at that level is possible
but not much fun: you'll stick on lots of rocks and there are some sharp ones.
Here are two possible shuttle contacts- haven't used either so I'm not recommending them. Stoney Creek Outfitters- 307-326-8750. Hack's Tackle- 307-326-9823. If you call, ask if they're still running trips through Northgate.
If fishing's your main interest, floating from Six Mile Gap (steep carry down, overnight camp), Corral Creek CG (no ramp, 1/4 mile carry) or Bennett Peak (launch ramp, campground) to Treasure Island are decent choices at this level.
Below Northgate, the worst parts at really low water (<450) are the braided cobble-bed reaches through the private ranches (A Bar A, Sanger). Easy to get stuck and the rocks are bloody slick.
Check the FS site for mileage and access info:
USDA Forest Service, Medicine Bow & Routt National Forests, Thunder Basin National Grassland - Recreation Activities